Golf swing training device



Feb. 18, 1969 G, p, ATKlNSON 3,428,325

GOLF SWING TRAINING DEVICE Filed Jan. 13, 1966 //00% slrefchob/e by about 5 /0/b. force Gorlond P. Atkinson Fig.| Y Wwm United States Patent O 3 Claims ABSTRACT F THE DISCLOSURE A golfers swing training club includes a handle member having gripping characteristics corresponding to those of a golf club handle and a soft rubber body connected thereto by a longitudinally elastic and laterally exible cord forming a club shaft. The soft rubber body weighs about 21/2-3 ounces and has a projected side area of about 8-10 square inches. The cord includes elastic strips encased in a sheath having clips squeezed around its ends. One end of the cord is inserted into an annular core member in the soft rubber body and then knotted. The other end of the cord is inserted into the handle member which is then crimped thereabout. The cord shaft is 100% stretchable by a force of about -10 pounds.

This invention relates to a training device and more specifically to a practice device for teaching proper swinging of a sport implement.

It is another object to provide a new and improved practice club for teaching proper swinging habits.

It is a further object to provide a practice golf club having a shaft adapted to flex in all directions lateral to its longitudinal axis.

It is an additional object to provide a practice golf club having a flexible shaft which is elastic permitting elongation thereof during the swinging of the club.

It is a further object to provide a practice golf club having a head comprising a soft mass of resilient material adapted to contact portions of the human body without discomfort and being of a size providing realistic air resistance characteristics during the swinging of the club.

It is a still further object of the invention to provide a practice golf club having a handle, a flexible, longitudinally elastic shaft, and a soft rubber-like head.

It is still a further object of the invention to provide a practice golf club having a head adapted for both lateral and longitudinal movement relative to the axis of the club whereby such head is displaceable from an optimum trajectory during swinging of the club by any forces being applied to the club in a direction or directions tending to reduce the efficient utilization of the forces being applied to the club.

It is still a further object of the invention to provide a practice golf club having a head adapted to respond to undesirable swinging forces in a manner detectable by the user both visually and by feel.

Additional objects and advantages of the invention will be readily apparent from the reading of the following description of a device constructed in accordance with the invention, and reference to the accompanying drawings thereof, wherein:

FIGURE 1 is a longitudinal view in elevation of a practice golf club embodying the invention and illustrating in broken lines the flexibility of the shaft section of the club;

FIGURE 2 is an enlargedview partially in elevation and partially in section of the handle and upper portion of the shaft of the practice golf club of FIGURE 1;

FIGURE 2-A is an enlarged view partially in elevation and partially in section of a lower end section of the shaft of the club together with its head;

ICC

FIGURE 3 is a cross-sectional view taken along the line 3--3 of FIGURE Z-A; and

FIGURE 4 is an enlarged view in section along the line 4-4 of FIGURE 2.

Referring to the drawings, a practice golf club 10 embodying the invention includes a handle 11, a flexible elastic shaft 12, and a head 13.

The handle 11 comprises an outer grip or body portion 14 having an outside surface 14a contoured to conform to the shape of a standard golf club handle, which, in the particular form illustrated, is a tapered circular shape. The grip portion 14 is formed of rubber or a rubber-like material tted over a sleeve 15 formed of a deformable tubular material such as steel. The grip portion may be molded on the `sleeve 15 or the sleeve :may be telescoped into the bore 16 of the handle and be held therein by a tight friction fit. A breather port or passage 20 extends through an upper end section 14 b of the handle portion into the upper end of the sleeve 15.

The shaft 12 is formed of a plurality of longitudinally extending, flexible, elastic strips 21 formed of a material such as rubber and bundled together in longitudinal parallel relationship within a woven sheath 22. The elastic strips 21 are held together and the sheath 22 is clamped around the elastic strips by split clips 23 squeezed around the sheath a short distance from each of its ends. The number and `size of the elastic strips 21 and the structure of the sheath 22 provides a shaft 12 of an elasticity such that a force ranging from 5 to 10 pounds applied to the shaft tending to stretch its ends apart elongates it substantially 100 percent. The sheath itself is stretchable so that it too may elongate within predetermined limits.

As illustrated in FIGURES 2 and 4, the shaft 12 is secured along its upper end section 12a within the handle 11 by crimping the sleeve 15 inwardly annularly at 24 thereby reducing the diameter of the sleeve around the sheath 22 and its enclosed bundle of elastic strips 21 so that the shaft is captured within the sleeve sufficiently tightly that the practice club may be swung with maximum probable force without pulling the shaft from the handle or effecting any appreciable movement of the shaft relative to the handle. In manufacture, the shaft 12 with the clip 23 engaged thereon is inserted into the sleeve 15 which is then crimped or constricted at 24 subsequent to which the grip 14 of the handle is either molded around the sleeve or the sleeve is inserted into it by any suitable means. The clip 23 may also serve to prevent withdrawal of the shaft from the sleeve since its outer diameter is greater than the internal diameter of the sleeve at its constriction 24.

As shown in FIGURES 2-A and 3 the head 13 of the practice club is adjustably secured on a lower end section Y 12b of the shaft 12. The head comprises a soft resilient eoA tubular casing 30 molded on or otherwise suitably secured, as by a cement layer 31, to an annular core or body 32 which is substantially shorter in length than the casing so that a downwardly opening cylindrical cavity 33 is formed within the casing between its lower end and the lower end 34 of the core. A bore 35 extends through the core along its axis to receive the shaft 12. The shaft *12, bel-ow the core and within the cavity 33, is tied to form a knot 40` which is engageable with a retainer washer 41 positioned around the shaft between the knot 40 and the lower end face 34 of the core. The knot 40 is larger than the bore 35 and the bore 42 through the Washer so that the knot will not be pulled through the washer and the core and the head 13 is held on the shaft under all normal predictable force conditions encountered during the swinging of the practice club. The shaft is preferably knotted -at a location to retain the head on the shaft with the lower end section 12a of the shaft being short enough that it is readily contained within the cavity 33. The use of the knot 40 in the shaft permits the position of the head 13 on the shaft to be adjusted so that the distance between the head and the handle is variable to permit use of the club by golfers of different heights and arm lengths.

The casing 30 of the head 13 is preferably formed of a soft cellular material such as a plastic or rubber which may repeatedly strike the body of the user of the practice club without discomfort to the user due to the large area of contact of the head with the body of the user. The casing preferably weighs within the range of approximately two and one-half to three ounces and has a projected side area, that is, the height of the casing rnultiplied by its diameter, of approximately eight to ten square inches. This preferred weight and size provides a club head which creates sufficient centrifugal force to provide the user with a realistic feel of the position of the club head during the swinging of the club. Also, the size of the head does not interfere with its normal movement through the air due to unrealistic resistance from the air. The core 32 is preferably formed of the substantially rigid though relatively light material such as some forms of wood or plastic.

The practice golf club is gripped and swung in a conventional manner. Obviously, the use of the club by various golfers for practice swinging will vary to the extent that the users grips and swings vary. Irrespective of the details of the particular grip and swing procedures employed by various golfers, the ultimate objective of each method used is the most efficient utilization of the energy applied to a golf club so that the club is moved with optimum force in the desired direction to most effectively strike a golf ball. The several forces which are combined to move a golf club through its complete swing are developed in a golfers body, arms, and wrists. By definition the terminology body shall also include the golfers legs. The ideal swing, that is the movement of the golf club from the beginning of the backswing through the end of the follow-through, comprises a smooth blending of the various forces generated by the golfer and applied to the club to produce the maximum force obtainable in the club head in the desired direction at the time of impact of the club head with the ball. Any random forces applied in directions which do not combine with properly directed forces to produce a maximum resultant force reduce the efficiency and effectiveness of a golfers swing.

The rocking and torsional movements provided by body action of a golfer are coordinated with his arm swing and wrist cocking and uncocking in such manner that the individual forces from each of these movements are applied to the golf club in the maximum cumulative degree possible to minimize the cancellation, in full or partially, of one force by another. The forces from the body action, the arm swing, and the wrist action preferably are all applied to the golf club in a common plane in which the handle and shaft of the club together move through the swing with the point of impact of the club head and the golf ball also lying in this plane. The resultant force with which the club head strikes the ball is preferably as near as practicable the sum of these individual forces. Obviously, random or transient forces applied from the body, arms, or wrists of the golfer to the handle of the club reduce the magnitude of the force being applied to the club head into the common plane and necessarily changes the direction and magnitude of the ultimate resultant force applied to a golf ball.

The practice golf club is held by a user with his hands gripping the handle 11 in his customary manner. The golfer moves the practice club through the back swing at the end of which the flexibility of the shaft -12 permits the club head 13 to swing beyond the position of a conventional club head relative to its handle until the head 13 strikes the golfer in the chest or shoulder. The relatively large surface area of the `soft casing of the head prevents bruising or other discomfort to the golfers body when the head strikes it. Of course, at the end of the back swing the direction of movement of the club by the golfer is changed starting the downswing to move the club from behind his body past his right side downwardly toward the normal ground position of a golf ball to be hit. During the downswing the centrifugal force resulting from the forces being applied to the handle causes the head of the club to swing at the end of the flexible elastic shaft 12 with elongation of the shaft occurring proportional to the magnitude of the resultant of the forces being applied to the handle. It may be considered during this swinging of the club by the golfer, that the golfers neck acts as the hub of a hypothetical wheel with his arms and shoulders rotating as spokes of the wheel about its hub. This hypothetical wheel thereby rotates within the previously discussed common plane in which the various forces generated by the golfer are preferably applied.

As the practice club passes the position at which impact between the club head and the ball normally occurs, the club handle, its shaft, and the point of impact with the ball on the club head preferably lie within the hypothetical wheel or common plane. Also the club handle, shaft, and point of impact on the club head preferably are in the same plane so that, considered in all directions, the club handle, shaft, and head are in longitudinal linear alignment at the point of impact of the club head with the golf ball. Since different golfers obviously do not apply the same magnitude of forces to the handle, the degree of elongation of the elastic shaft 12 varies with each golfer and thus several practice swings are necessary to determine the proper length of the shaft 12 to position the head 13 correctly for the golfers swing. The shaft preferably elongates at the position of impact to a length at which the head 13 is substantially at the position of the head of a conventional club when so swung. The length of the shaft 12 is adjusted by alteration of the position of the knot 40 in the shaft below the core 32 within the cavity 33 of the club head. Obviously, the head 13 should not be so positioned that it strikes the ground when the club is swung `by a golfer nor should it be positioned such that it is too far from the ground location of a golf ball normally hit by the golfer.

The golfer continues his swing beyond the point of normal impact through the completion of the followthrough. At the termination of the follow-through portion of a swing, the flexibility of the shaft 12 again permits the head 13 to continue its path of travel striking the golfers `body generally in the vicinity of his chest or shoulder on the side of his body opposite which the follow-through swing passes. The casing 30 strikes near the chest or right shoulder of a right-handed golfer. Similarly as previously described. the area and softness of the casing prevents injury or even discomfort to the golfer when struck Lby the head.

From the time that the club head attains sufficient velocity for centrifugal force to maintain the shaft straight in the early stages of the downswing through the end of the follow-through, the flexibility and elasticity of the shaft 12 allowing it to enlongate and to ex in any direction transverse to its longitudinal axis permits the shaft and particularly the club head 13 to be affected by undesirable forces tending to displace the club head and shaft from the preferred common plane, as previously discussed. Forces which are applied in directions not contributing to maintaining the shaft and head in the common plane `and in longitudinal alignment move the club head in the direction of the resultant of the forces. The practice club, therefore, does not absorb undesirable forces with a resultant reduction of the maximum available force and possible misdirection of the club without clearly identifiable evidence of the causes of an improper swing as does a conventional club and a golfer can analyze his actions. Since the shaft and club head are affected by one or several undesirable forces, such force or forces displace the head from its preferred path, the head moving out of alignment with the handle with visual evidence being discernible by the golfer of the undesirable force or forces he is generating in developing his swing. The golfer can both see and feel the movement of the shaft and head from the desired trajectory yand thus is provided an opportunity to immediately identify errors he is introducing into his swing. With the golfers errors being evident both to feel and sight, he may thus practice with the club until he eliminates the undesirable habit or habits which are introducing the improper forces into his swing. Repeated swinging of the practice club along with analyzing and correcting his swing until a faultless swing pattern repeatedly produced `develops and co-ordinates the golfers movements until they become essentially automatic.

It will now be seen that a new and improved golf device has been described and illustrated.

It will be further seen that a new and improved practice golf club for teaching proper swinging habits has been described and illustrated.

It will additionally be seen that the practice golf club includes a handle, a flexible elastic shaft, and a head formed of soft resilient material.

It will additionally be seen that a practice golf club embodying the invention has a shaft section which is flexible in all planes permitting it to ex in any direction.

It will also be seen that the shaft of the practice golf club is elastic and thus elongates when subjected to centrifugal force during the swinging of the club. It will be further seen that the club has a head comprising a soft mass of resilient material permitting it to strike the human body without discomfort and being sized to produce realistic air resistance when swung,

It will be further seen that the head of the practice golf club is displaceable from an optimum trajectory during a swing or by a force or forces applied to the club in a direction or directions tending to change the direction and reduce the magnitude of the forces being applied to the club head from the optimum direction and magnitude.

The principles and functional components of the practice golf club are readily applicable to other sports apparatus which is swung for the purpose of striking a lball. For example, practice tennis rackets and baseball fbats may incorporate the principles of the invention. 1n applying the invention to tennis, a typical tennis racket handle is simulated, a flexible elastic shaft is connected with the handle, and a head duplicating the weight and air resistance characteristics of a tennis racket is connected with the shaft. The length of the shaft is adjusted to that of a typical racket. The practice racket is used to analyze a players swing and .aid in subsequently correcting faults in such swing.

The foregoing description of the invention is explanatory only, and changes in the details of the construction illustrated may be made by those skilled in the art, within the scope of the appended claims, without departing from the spirit of the invention.

What is claimed and desired to be secured by Letters Patent is:

1. A golf swing training device comprising: a handle section of a handle of a golf club and an inner tubular sleeve of substantially rigid deformable material telescopically fitted within said grip portion extending through a substantial portion of the length of said grip portion; a shaft having first and second ends, said shaft being longitudinally elastic throughout its length and laterally flexible in a plurality of directions throughout its length, the first end of said shaft being telescopically fitted into said sleeve at the lower end of said handle, said sleeve being annularly crimped around the first end of said shaft to secure said first end of said shaft within said sleeve; said shaft comprising a plurality of longitudinally elastic strips bundled together in substantially parallel relationship Within a woven longitudinally stretchable sheath, said sheath being secured around said elastic strips by clips secured around said sheath near opposite ends of said shaft, one of said clips being on said first end of said shaft within said sleeve of said handle between the center of said handle and said crimped sec-tion of said sleeve, said crimped section having a diameter less than the maximum diameter of said clip Within said sleeve on said shaft; and a head secured on the second end of said shaft, said head having an annular central core of Substantially rigid material slidably engaged on said shaft, said second end of said shaft having a. knot therein and a tubular casing of soft material telescopically secured on said core, said casing being longer 'than said core and providing a cylindrical cavity within said head .for receiving and concealing said knot on said second end of said shaft.

2. A golf training device as defined in claim 1 including a retainer washer positioned on said shaft Awithin said cavity of said head between said knot and said core.

3. A golf training device as defined in claim 1 wherein said casing weighs within the range of about two-and-one- Ihalf ounces and three ounces and has a projected side area of about eight to ten square inches and said shaft is elongatable about one hundred percent when subjected to a `stretching force at said head of about five to ten pounds.

References Cited UNITED STATES PATENTS 2,447,967 8/1948 Stone 273-77 2,979,858 4/1961 Holman 46-52 439,297 10/1890 Heyder 273-95 1,471,794 10/1923 Leven 273-193 X 2,765,170 10/ 1956 Brown 273-95 X 2,848,234 8/1958 Brandon 273-194 X 3,031,191 4/1962 Bonang 273-95 3,229,980 1/1966 Silberman 273-193 X FOREIGN PATENTS 244,013 12/ 1925 Great Britain. 472,237 9/ 1937 Great Britain.

GEORGE J. MARLO, Primary Examiner.

U.S. Cl. X.R. 

